Electrical devices often include components that are provided on a plug-in circuit card and attached to the device by inserting the card into a connector on a mother board or backplane within the device. For example, many computer designs have processor boards, memory boards, and other types of printed circuit cards that are connected to the device by insertion into a connector on a mother board or backplane.
In some devices, several circuit cards can be connected to a common backplane or motherboard. For example, each circuit card may be provided with a bus connector that is configured to mate with a corresponding electrical connector mounted to the backplane or motherboard. To facilitate proper alignment and installation of several circuit cards, the electrical device may have a chassis having a plurality of slots into which the cards can be inserted.
In some conventional card chassis and/or card cages, the slots for holding the cards have approximately the same dimensions so as to be configured to hold circuit cards having the same dimensions. For example, the slots may be configured to hold VME standard cards, which have standard dimensions, including a depth of 160 mm.
However, in some applications, circuit cards having dimensions other than a standard VME card may be used. For example, some cards may have a depth of 160 mm but may have a variety of heights. Other card sizes also exist, including for example, standard cards having depths that increase from 160 mm in 60 mm increments (e.g., depths of 220 mm, 280 mm, etc.), as well as custom circuit cards having custom depths, which may be greater or less than 160 mm. In the latter case, for example, the assignee of the present application, makes a custom card for use in aerospace applications that has a height of about 184.5 mm, as measured from proximate where the ejection levers mount on the card to the bottom of the card containing the connectors. For the purposes of this disclosure, the depth of a circuit card refers to its dimension in the direction of insertion into the card chassis, e.g., the distance between the end of the card that has the connector (e.g., bus connector) and the opposite end of the card proximate where the levers connect to the cards. The height of a circuit card refers to its dimension measured along a length of a card slot (e.g., perpendicular to the direction of insertion).
Various approaches have been taken to provide adapters that permit cards of differing heights to be used within a single card chassis or card cage assembly. For example, partitions have been provided for use with a card cage assembly to permit the use of smaller cards (e.g., cards having a height of 100 mm) in larger sized card cages (e.g., cages having card slots configured to receive cards having height of 233.35 mm). However, a disadvantage of some partition configurations is that they occupy space that may otherwise be used for a circuit card. In addition, such partitions do not permit the assembly to be modified to hold circuit cards of differing depths. Further, some such partition designs are relatively complex.
To accommodate circuit cards of differing depths, adapters that come in standard size increments (e.g., 60 mm, 120 mm, etc.) have been used. These adapters connect to the connectors on the circuit cards to add depth to a smaller, standard depth card.
As mentioned above, some circuit cards may have a depth that differs from standard circuit card depths. It may therefore be desirable to provide an assembly for holding circuit cards (e.g., a card chassis) that may be configured to hold cards of varying depths and to permit such cards of varying depths to engage with corresponding connectors on a backplane or motherboard. It also may be desirable to provide such an assembly where ejection of the circuit cards, regardless of their depth, may be accomplished via conventional ejection levers typically provided on circuit cards.
It may be further desirable to provide a card cage configuration that can hold circuit cards of varying depths that is relatively simple in design and use.